Qwen3.5-Flash vs Step 5 Preview
Step 5 Preview leads Qwen3.5-Flash on coding, 61.1 to 41.1 on the Vibe Coding Index, and Qwen3.5-Flash costs 10.4x less per output token ($0.26 vs $2.70 per million). Updated October 22, 2026; 28 benchmarks have a result for both.
Qwen3.5-Flash or Step 5 Preview: which to pick
Pick Step 5 Preview for coding: it scores 61.1 on the Vibe Coding Index against 41.1 for Qwen3.5-Flash.
Pick Qwen3.5-Flash for output tokens 10.4x cheaper ($0.26 vs $2.70 per million).
- Shared results
- 28
- Qwen3.5-Flash only
- 27
- Step 5 Preview only
- 33
- Like-for-like categories
- 5 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
Step 5 Preview
Step 5 Preview scores 61.1 against 41.1.
2 and 4 benchmarks behind the scores
Intelligence
AA Intelligence Index
No call
Only Step 5 Preview has a AA Intelligence Index result, 43.7.
Directional only
Reasoning
GPQA Diamond
No call
Only Qwen3.5-Flash has a GPQA Diamond result, 82.8%.
Directional only
Math
AIME
No call
Only Qwen3.5-Flash has a AIME result, 92.5%.
Directional only
Knowledge
MMLU Pro
No call
Only Qwen3.5-Flash has a MMLU Pro result, 84.1%.
Directional only
Long documents
Listed context window
Step 5 Preview
Step 5 Preview takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Qwen3.5-Flash
Qwen3.5-Flash $0.0002, Step 5 Preview $0.0024 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Qwen3.5-Flash has the number, $0.40.
Directional only
At a glance
- Coding index
- Qwen3.5-Flash 41.1 from 2 benchmarks, Step 5 Preview 61.1 from 4 benchmarks.
- Widest category
- Coding, 34.2 points apart on average over 5 shared benchmarks.
- Widest single gap
- LMArena WebDev: React: Qwen3.5-Flash 1229 against Step 5 Preview 1583, 58.9 points apart on a 0 to 100 scale.
- Output price
- Qwen3.5-Flash $0.26 against Step 5 Preview $2.70 per million output tokens, 10.4x apart.
- Context window
- Qwen3.5-Flash takes 1M tokens, Step 5 Preview 1.05M.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Qwen3.5-Flash | Bars | Step 5 Preview | Ties |
|---|---|---|---|---|
| Coding | 0 | 5 | ||
| Reasoning | 0 | 3 | ||
| Math | 0 | 2 | ||
| Knowledge | 0 | 4 | ||
| General | 0 | 14 | ||
| All shared boards | 0 | 28 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index05
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 85.6% | Only Step 5 Preview measured |
| LMArena WebDev | 1244 | 1567 | Step 5 Preview |
| LiveCodeBench (Vals AI) | 83.3% | Not measured | Only Qwen3.5-Flash measured |
| SWE-bench Verified (Vals AI) | 64.4% | Not measured | Only Qwen3.5-Flash measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 31.8% | Only Step 5 Preview measured |
| Vibe Code Bench (Vals AI) | Not measured | 70.4% | Only Step 5 Preview measured |
| Code migration (Vals AI) | Not measured | 39.0% | Only Step 5 Preview measured |
| IOI (Vals AI) | Not measured | 38.1% | Only Step 5 Preview measured |
| SWE-bench Multimodal (Vals AI) | Not measured | 40.8% | Only Step 5 Preview measured |
| SciCode | Not measured | 58.9% | Only Step 5 Preview measured |
| ALE-Bench | 265.9 | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text: coding | 1412 | 1485 | Step 5 Preview |
| LMArena Text: software and IT | 1416 | 1473 | Step 5 Preview |
| LMArena WebDev: React | 1229 | 1583 | Step 5 Preview |
| LMArena WebDev: HTML | 1291 | 1556 | Step 5 Preview |
| LMArena WebDev: from an image | Not measured | 1550 | Only Step 5 Preview measured |
| Neither model has a result on the other 23 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 43.7 | Only Step 5 Preview measured |
| Epoch Capabilities Index | 143.5 | Not measured | Only Qwen3.5-Flash measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index11 boards, none shared
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench research | Not measured | 72.8% | Only Step 5 Preview measured |
| LiveBench browser | Not measured | 24.0% | Only Step 5 Preview measured |
| LiveBench long agentic | Not measured | 27.5% | Only Step 5 Preview measured |
| SREBench (Vals AI) | Not measured | 0.4% | Only Step 5 Preview measured |
| Finance Agent (Vals AI) | Not measured | 50.7% | Only Step 5 Preview measured |
| Tax Agent Bench (Vals AI) | Not measured | 27.3% | Only Step 5 Preview measured |
| Legal Research Bench (Vals AI) | Not measured | 40.4% | Only Step 5 Preview measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 57.1% | Only Step 5 Preview measured |
| BioMysteryBench (Vals AI) | Not measured | 67.4% | Only Step 5 Preview measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 2.9% | Only Step 5 Preview measured |
| Vals Science Index | Not measured | 29.6% | Only Step 5 Preview measured |
| Neither model has a result on the other 30 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index03
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| GPQA Diamond | 82.8% | Not measured | Only Qwen3.5-Flash measured |
| LiveBench reasoning | Not measured | 83.8% | Only Step 5 Preview measured |
| MysteryMechanism (Vals AI) | Not measured | 18.5% | Only Step 5 Preview measured |
| MMMU Pro (Vals AI) | 81.9% | Not measured | Only Qwen3.5-Flash measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 46.5% | Only Step 5 Preview measured |
| GPQA Diamond (Epoch AI run) | 82.3% | Not measured | Only Qwen3.5-Flash measured |
| Chess puzzles | 14.0% | Not measured | Only Qwen3.5-Flash measured |
| Mystery game puzzles | 20.0% | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text: hard prompts | 1403 | 1461 | Step 5 Preview |
| LMArena Text: expert | 1407 | 1485 | Step 5 Preview |
| LMArena Text: hard prompts in English | 1409 | 1454 | Step 5 Preview |
| LMArena Vision: diagrams | Not measured | 1308 | Only Step 5 Preview measured |
| LMArena Vision: homework | Not measured | 1265 | Only Step 5 Preview measured |
| Neither model has a result on the other 9 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| AIME | 92.5% | Not measured | Only Qwen3.5-Flash measured |
| OTIS Mock AIME | 84.4% | Not measured | Only Qwen3.5-Flash measured |
| FrontierMath, tiers 1 to 3 | 18.2% | Not measured | Only Qwen3.5-Flash measured |
| ProofBench | Not measured | 42.0% | Only Step 5 Preview measured |
| LMArena Text: math | 1407 | 1458 | Step 5 Preview |
| LMArena Text: mathematical work | 1413 | 1460 | Step 5 Preview |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| MMLU Pro | 84.1% | Not measured | Only Qwen3.5-Flash measured |
| LegalBench (Vals AI) | 84.3% | Not measured | Only Qwen3.5-Flash measured |
| CaseLaw (Vals AI) | 56.0% | Not measured | Only Qwen3.5-Flash measured |
| CorpFin (Vals AI) | 63.6% | Not measured | Only Qwen3.5-Flash measured |
| TaxEval (Vals AI) | 72.2% | Not measured | Only Qwen3.5-Flash measured |
| MortgageTax (Vals AI) | 67.4% | Not measured | Only Qwen3.5-Flash measured |
| MedCode (Vals AI) | 33.0% | Not measured | Only Qwen3.5-Flash measured |
| SimpleQA Verified | 20.3% | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text: science | 1415 | 1454 | Step 5 Preview |
| LMArena Text: medicine and healthcare | 1407 | 1439 | Step 5 Preview |
| LMArena Text: legal and government | 1398 | 1437 | Step 5 Preview |
| LMArena Text: business and finance | 1394 | 1435 | Step 5 Preview |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench design | Not measured | 76.9% | Only Step 5 Preview measured |
| Neither model has a result on the other 8 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index014
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench data analysis | Not measured | 63.5% | Only Step 5 Preview measured |
| Public Benefits Bench (Vals AI) | Not measured | 58.1% | Only Step 5 Preview measured |
| SAGE (Vals AI) | 42.5% | Not measured | Only Qwen3.5-Flash measured |
| MedScribe (Vals AI) | 70.6% | Not measured | Only Qwen3.5-Flash measured |
| Long context reasoning (AA-LCR) | Not measured | 88.3% | Only Step 5 Preview measured |
| DTBench | 82.9% | Not measured | Only Qwen3.5-Flash measured |
| LMCA | 29.1% | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text | 1397 | 1440 | Step 5 Preview |
| LMArena Text: instruction following | 1374 | 1438 | Step 5 Preview |
| LMArena Text: creative writing | 1343 | 1409 | Step 5 Preview |
| LMArena Vision | Not measured | 1265 | Only Step 5 Preview measured |
| LMArena Text: English | 1404 | 1447 | Step 5 Preview |
| LMArena Text: non-English | 1385 | 1428 | Step 5 Preview |
| LMArena Text: Chinese | 1445 | 1500 | Step 5 Preview |
| LMArena Text: German | 1390 | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text: Japanese | 1369 | 1383 | Step 5 Preview |
| LMArena Text: Korean | 1344 | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text: French | 1413 | 1438 | Step 5 Preview |
| LMArena Text: Spanish | 1400 | 1441 | Step 5 Preview |
| LMArena Text: Russian | 1380 | 1433 | Step 5 Preview |
| LMArena Text: Polish | 1376 | Not measured | Only Qwen3.5-Flash measured |
| LMArena Text: multi-turn | 1393 | 1437 | Step 5 Preview |
| LMArena Text: longer queries | 1392 | 1449 | Step 5 Preview |
| LMArena Text: writing and language | 1369 | 1425 | Step 5 Preview |
| LMArena Text: entertainment and media | 1347 | 1412 | Step 5 Preview |
| LMArena Vision: English | Not measured | 1290 | Only Step 5 Preview measured |
| LMArena Vision: reading text | Not measured | 1282 | Only Step 5 Preview measured |
| Neither model has a result on the other 19 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Qwen3.5-Flash | Step 5 Preview | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Qwen3.5-Flash costs less
Repository review
50K input + 3K output tokens
Qwen3.5-Flash costs less
Agent loop
200K input + 10K output tokens
Qwen3.5-Flash costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Qwen3.5-Flash | StepFun Step 5 Preview |
|---|---|---|
| Maker | Qwen | StepFun |
| Weights | No public weights listed | Open weights |
| Released | February 25, 2026 | October 8, 2026 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $0.065 | $1.00 |
| Output $/Mtok | $0.26 | $2.70 |
| Coding index | 41.1 | 61.1 |
| Independent measurements behind it | 2 | 4 |
| Cost per solved task | $0.40 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Qwen3.5-Flash better than Step 5 Preview for coding?
Pick Step 5 Preview for coding: it scores 61.1 on the Vibe Coding Index against 41.1 for Qwen3.5-Flash. Pick Qwen3.5-Flash for output tokens 10.4x cheaper ($0.26 vs $2.70 per million).
Which is cheaper, Qwen3.5-Flash or Step 5 Preview?
Qwen3.5-Flash costs $0.065 per million input tokens and $0.26 per million output tokens; Step 5 Preview costs $1.00 and $2.70. Cost per solved task is known for Qwen3.5-Flash only.
Which has the bigger context window, Qwen3.5-Flash or Step 5 Preview?
Step 5 Preview, with 1.05M tokens against 1M.
How many benchmarks is the Qwen3.5-Flash vs Step 5 Preview comparison based on?
28 benchmarks have a result for both models as of October 22, 2026. Qwen3.5-Flash's coding index rests on 2 independent benchmarks and Step 5 Preview's on 4. Where only one model has a result, the page says so instead of naming a winner.